Screw-holding screw driver



Oct. 10, 1961 "w. E. LANDEAU 3,003,

' SCREW-HOLDING SCREW DRIVER Filed June 22, 1959 INVENTORI WARNER E;LANDEAU I B Y I ATTORNEY 3,003,528 SCREW-HOLDING SCREW DRIVER Warner E.Landeau, Racine, Wis. (3500 Parsifal, N.E., Albuquerque, N. Mex.) FiledJune 22, 1959, Ser. No. 821,954 3 Claims. (11. 145-50) This inventionrelates to screw drivers and more particularly it relates to anattachment for preferably a power type of screw driver wherein the screwcan be held firmly by the screw driver bit prior to and during the timethat the screw is being run into its position.

It is an object of this invention to provide a screw driver whichpositively holds the screw while the latter is being screwed intoposition and which has a movable jaw which increased its grip on thescrew in response to screwing action.

Another object of this invention is to provide a screwholding screwdriver bit which employs the movable jaw to apply torque on the screw,and which is particularly adaptable to powered screw drivers, and whichcan be made in the form of an attachment for powered screw drivers.

Still another object of this invention is to provide a screw-holdingscrew driver bit wherein the greater the torque applied to the screw,the greater the holding force becomes.

Still another and more particular object of this invention is to providea cam lock or other positive lock type of screw-holding screw driver bitsuch that the screw being worked upon will be securely held, not onlyprior to engagement with the workpiece, but also during the time thatthe screw is being screwed into its fully seated position. Other objectsand advantages will become apparent upon reading the followingdescription in conjunction with the accompanying drawings wherein:

FIG. 1 is a top view of a preferred embodiment of a screw driver bitmade according to this invention and showing part thereof in section,and also showing the end of a power screw driver in dotted lines.

FIG. 2 is a side View of the screw driver bit shown in FIG. 1, and alsoshowing a fragment of a screw assembled therewith.

FIG. 3 is a front end view of the bit shown in FIGS. 1 and 2, but withthe camming ring removed.

FIG. 4 is a front end view similar to that of FIG. 3, but with theone-half of the bit in a different position.

The same reference numerals refer to the same parts among the severalviews.

The drawings show what may be termed a screw driver attachment 10,assembled with an end of a handle or power screw driver 11 shown onlypartly and in dotted lines, and also assembled with a clutch, which isalso shown in dotted lines. It will, of course, be understood that thescrew driver 11, or handle 11, whichever it may be, and the clutch 12,are both conventional and are merely shown for explanatory purposesrelating to the attachment or bit 10, which forms the instant invention.The attachment or hit 11) is composed of a shank 13 having a reducedportion 14 with a flat face 16 for driving attachment to the clutch 12,or the handle or powered screw driver 11, as preferred and in anyconventional manner. The shank 13 is made essentially in two halves 17and 18, which are pivoted together by means of a pin 19 passing throughthe forward ends of the halves 17 and 18 as shown. Thus the shank or bithalf 17 is fixed while the shank or bit half 18 is movable about the pin19, which is the fulcrum. In this arrangement, it will thus be seen thatthe shank 13 has a half cut-out 21, which extends from the shoulder orwall 22, to the forward or screw-holding end of the attachment 10, andit nited States Patent extends for the semi-circular cross section ofthe shank 13. In this arrangement, it will now be seen and mentionedthat a heel or end 23 of the half 18 abuts the wall or shoulder 22 toprevent the end 13 from moving or pivoting excessively out of relationwith the stationary half 17. A ring or actuator 24 is slidably disposedover the shank 13 in the position shown so that the ring can slide, forinstance, between the pin 19 and a cam follower portion 26 on the rearend of the bit half 18. It will be further seen that the rear end of thering 24 has a cam or actuating surface 27, which is, of course facedtoward the cam follower 26, and it will thus be understood that uponSliding the ring 24 rearwardly on the shank 13, the cam 27 will engagethe cam follower 26 to displace the latter radially inwardly withrespect to the edge of the shank 13, and thus pivot the half 18 aboutthe pin 19.

FIGS. 2 and 3 show the position of the bit jaws 28 and 29, which are onthe bit halves 17 and 18 respectively. In this position, the jaws 28 and'29 are aligned with each other, as seen in FIG. 3, for instance, and inthis position the screw 31 can be positioned, as shown in FIG. 2 withthe jaws 28 and 29 disposed within the screw slot 32 in the usual mannerof assembly between screw and screw driver bit. Then, when the actuator24 is slid rearwardly on the shank 13, the cam 27 engages the camfollower 26 to cause the bit jaw 29 to move downwardly, as shown in FIG.4, and the jaw 29 is thus offset with respect to the fixed position ofthe jaw 28. In this manner, the jaws 28 and 29 bind upon the screw 31 inthe slot 32, and thus securely hold the screw 31 to the screw driver. Inthis arrangement of offsetting the jaw 29 to a lower position, as viewedin FIG. 4, the jaws 28 and 29 clamp onto the screw 31 more securely in aright hand screwing action, so that the screw driver holds the screwmore firmly in accordance with the amount of screwing torque beingapplied at the point of the jaws 28 and 29. Also, the movable jaw orhalf 18 serves as a torque-transmitting member since it is connected atpin 19 and since the sleeve 24 abuts the rear portion of the half 18when the latter is offset by the screwing action as indicated in FIG. 4.Of course, the cam lock is so designed that the screw driver can beeasily removed from the screw 31 after the latter is set into positionas desired, and this, of course, is accomplished merely by sliding thering or actuator 24 forwardly to release the pivotal half 17 from itslocked position on the screw 31. It should also be mentioned that thisparticular invention finds particular application in screwing woodscrews into position, since the wood screw can be easily placed onto thejaws 28 and 29 and lock thereon, and then, where a powered screw driveris used, the screw driver can be operated and the screw brought up toposition and run down to its final seated position, at which time theclutch will automatically operate to relieve further screwing action onthe screw 31, so that the attachment 10 will not be rotated beyond apredetermined torque, which is the time when the screw 31 is fullyseated, as desired.

While a specific embodiment of this invention has been shown anddescribed, it will be obvious that certain changes can be made in theembodiment, and the invention, therefore, be limited only by the scopeof the appended claims.

What is claimed is:

l. A screw driver for positively holding a screw in the slot of thelatter, comprising a shank, a screw-slot engaging bit on one end of saidshank and being partitioned along the length of said shank into twohalf-portions consisting of a fixed bit half-portion on one side of saidbit and a movable bit half-portion on the other side of said bit, a pinextending through said portions in a direction transverse to thecenter-line plane of partition and being disposed adjacent said one endand with said movable bit portion being movable transverse to the slotof the screw for clamping the screw at said slot with the free ends ofboth said bit portions, and a sleeve on said shank and fully disposedover the other end of said movable bit portion, said sleeve and saidother end of said movable bit portion including camming surfaces in sliding contact for pivoting and securing said movable bit portion in apivoted position of clamping on said screw, said camming surface on saidmovable bit portion being disposed to the side thereof located in thedirection which said free end thereof moves for clamping and with saiddirection being counter-clockwise when viewed from said free end.

2. A screw driver for positively holding a screw in the slot of thelatter, comprising a cylindrical shank, one end of said shank beinglongitudinally separated into two halves and including a fixed bitportion on one side thereof and a movable bit portion on the other sidethereof diametrically opposite said one side and being pivotallyattached to said fixed bit portion intermediate the ends of said movablebit portion for movement transverse to the slot of the screw forclamping the screw at said slot with the free ends of both said bitportions, the other end of said movable bit portion being of a radiusslightly less than that of said fixed bit portion and including aportion projecting radially beyond the circumference of said other endand presenting a cam follower, and a cam ring of an internalcircumference snugly slidable on said shank intermediate said free endsand said cam follower for engaging said cam follower to thereby pivotsaid movable bit portion into clamping relation with said screw.

3. A screw driver for positively holding a screw in the slot of thelatter, comprising a cylindrical shank, one end of said shank beinglongitudinally separated into two portions with a planular face disposedlongitudinally of said shank and said shank including a screw-slotengaging fixed bit portion on the free end of said shank, said shankalso including a movable bit portion pivotally attached to said fixedbit portion immediately adjacent said free end and the free end of saidmovable bit portion for movement in a direction parallel to said faceand out of alignment with said fixed bit portion and transverse to theslot of the screw for clamping the screw at said slot with said freeends of both said bit portions, the other end of said movable bitportion being of a radius slightly less than that of said fixed bitportion and including an end projecting beyond the circumference of saidshank to present a cam follower, and a sleeve slidably mounted on saidshank and being disposed only intermediate the pivot point and said camfollower and including a camrning surface faced toward said cam followerfor engaging said cam follower to thereby pivot said movable bit portionout of alignment with said fixed bit portion for a clamping relationwith said screw, the internal circumference of said sleeve being snugwith the corresponding surface of said fixed bit portion and being of aradius slightly more than that of said other end of said movable bitportion for limiting movement of the latter during screwing action.

References Cited in the file of this patent UNITED STATES PATENTS1,627,301 Wood May 3, 1927 1,699,306 Miller Jan. 15, 1929 1,915,546Muller June 27, 1933 2,304,703 OLeary Dec. 8, 1942 2,737,988 Gearhart etal Mar. 13, 1956

